Which home theater receiver is better?
Denon 3300 or the Marantz 6200 ?

I'm going with Marantz, but more because I love the quality of the brand. I've got a 1979 model 2238B stereo reciever in my room that is still in great working order and is louder than any thing else i own (I have guitar amps that have been shamed by this thing...)

I've worked with and around both brands for 2 years now and my judgment is this:

Marantz makes a more solid receiver, and it looks better...but people tend to buy more Denon and they break ALL the time (I am a service man)

Denon makes the best DVD players hands down, except the new 5disc which is a pile of poo (seriously almost every one we sell comes back broke)

I personally have a Marantz 6300 (just upgraded from 5200), Denon DVD-1600, and B&W speakers.

If you are thinking in terms of sound quality, both are decent receivers that can deliver a satisfying listening experience. Which sounds better to you will depend on your hearing, your listening bias/preferences, and your associated equipment. Because sound is such a subjective area, questions like these often come down to popularity polls---especially when the receiver is considered outside the context of the speakers with which they will be mated.

As to failure rates, while this is an objective question, obtaining the necessary data to answer the question is difficult. Denon outsells Marantz so looking only at absolute numbers can be misleading. What’s more important is the percentage of failures WRT units produced. Generalizing across a brand can also be problematic as manufactures can have problems with one model and not others.

I think both are well built and should give you years of trouble free operation. Of course, there is always the risk of getting a lemon—that’s when store return policies and warranties become important. My advice would be to try both in your home and go with the one you like better.

Between myself, my brother, and three of our friends, we have the Denon 4800, 4802, and three 3200's and each unit has performed very well! I'm a Denon fan.

My parents have the Marantz 5000 (we actually didn't like the sound on the 7000 at the time) and they've been happy with that as well. I think I would still go with the Denon though.